1. Field of the Invention
The present invention pertains to photographing objects through an optical image-enlarging instrument and, more particularly, to photographing the human eye through the microscope of a slit lamp.
2. Discussion of the Prior Art
Slit Lamps are conventionally utilized by opthalmologists to examine the human eye by projecting a slit of light into the eye of a subject through an optical system. The optical system includes various optical components for controlling the configuration and size of the light beam as well as circuitry to control the intensity of the lamp. The opthalmologist examines the eye of the subject illuminated by the light beam through a microscope mounted adjacent the optical system, and it is frequently desirable for the opthalmologist to record the image of the eye viewed through the microscope for various reasons, such as to provide a record of the progress of a disease, deterioration of a part of the eye or treatment of the eye. In the past, the opthalmologist has recorded the images of the eye by sketching the image by hand, this method having many obvious disadvantages including being inaccurate and time consuming.
In order to facilitate the recording of images of an eye being examined, slit lamps have been modified to permit photographs of the eye to be obtained. Such modified slit lamps, as exemplified by U.S. Pat. Nos. 3,519,338; 3,591,262; 3,652,153; and 3,762,803 have had one or more of the disadvantages of the photographic apparatus being integrally combined with the slit lamp and, therefore, increasing cost and complexity of the modified slit lamp while reducing flexibility and universal use with various types of slit lamps, of requiring an additional light source to provide a flash of light through the optical components to the eye, of dividing the light along the observation axis to provide both viewing and photographing beams, of not photographing the same image viewed by the opthalmologist through the microscope and of requiring additional optical components to enlarge the image of the eye and direct the image to a photographic film.
It has been proposed, as exemplified by U.S. Pat. No. 3,292,490, to take photographs of an image viewed through a binocular microscope by using a camera mounted on one ocular of the microscope having an automatic shutter operated in response to light at the other ocular; however, since both oculars are occupied, the operator cannot view the object to be photographed simultaneously with the actual photographing process. Thus, the object to be photographed must be properly positioned or otherwise placed in a desirable condition for photographing by viewing through one of the oculars of the microscope; and, thereafter, the operator must mount the light sensing attachment on the ocular prior to operating the shutter of the camera. This operation is both cumbersome and time consuming and, furthermore, prevents the operator from detecting movement or other change of the object during the interim between positioning of the object and taking of the photograph.